#include<iostream>


class Singletion
{
private:
    static Singletion _sing;
    int _data = 10;
    Singletion(){}
public:
    Singletion& operator=(const Singletion&) = delete;
    static Singletion* get_instance()
    {
        return &_sing;
    }

    int get_data()
    {
        return _data;
    }
};

Singletion Singletion::_sing;

int main()
{
    std::cout<<Singletion::get_instance()->get_data()<<std::endl;
    return 0;
}